Comment 3 for bug 720066

Yes, I'd like that too. Although I use English locale, I cannot stand 12h format.
We don't actually need dconf as dependency.
GSettings from glib uses dconf as default backend.
We can use gnome.introspection to access the settings and set a hook for changes.
I attached a patch.
It works when the indicator-datetime format setting is set to 12h or 24h. In the other cases is uses the default locale as now.
It also fixes a small bug: when the time has 0 minutes these are stripped away currently.